Siren



R. DUNCAN 2,220,222

SIREN Filed Sept. 29, 1937 i60 Jz/efzfor 65 Eobefz Ea/,racen 56 gy@ @gf/7%@ Patented Nov. 5, 1940 UNITED l'sl'rxrrzs ISIREN Robert Duncan, Chicago, Illf, assigner to Federall Electric Company, Inc., Chicago, Ill., a corporation of New York Application September 29, 1937, Serial No.l 166,452 I 4 claims. cl.1777) The present invention relates to a combined sonic-visual signalling device for use on vehicles in order to warn pedestrians or other vehicles.

It is an object of the present invention to provide a new signalling and warning apparatus of improved and simplified construction adapted for use on vehicles requiring the right-of-way on thev highway, such as ambulances, re engines and police vehicles, which device is particularly adaptable formounting exteriorly thereof in a position exposed to weather conditions.

The present invention r lates more particularly to a siren type of signal 'ng device of the sort shown in LUnited States Letters Patent No. 2,172,413, issued September l2, 1939, on the invention of William W. Scott, wherein the sound effect is derived from a siren having a central .rotor or impeller arranged to drive columns of air radially outwardly through apertures or ports which are rapidly opened and closed. This type of sound-making device is .conventionally arranged so that the sound-producing ports or apertures are arranged annularly about the axis of the rotor, as-aresult of -which the characteristic sound effect :produced by the siren issues outwardly in all directions therefrom.

Vehicle signals, on the other hand,'are desirably arranged to direct the soundforwardly of the vehicle. exterior of the device, and more particularly on the upper portions thereof, are especially subject to the accumulation of foreign matter, such as sleet and moisture. Thus, under adverse winter conditions, the rotor may become frozen in the region of the ports or apertures when the unprotected device is mounted in a position accessible to the weather.

It is accordingly a purpose. of the present invention to provide a novel combined siren and visual warning signal in which the siren is completely protected against weather conditions and in which the sound produced thereby may be directed forwardly of the vehicle. A i

An additional object of the present invention is to provide a signal warning device of the above type wherein the sonic effect and the visual effect Moreover, siren -ports situated on the' sound chamber; to provide a siren wherein tne air inlet is positioned completely on the underside of the unit and protected against ingress of foreign matter; and to produce la simplified and compact arrangement of a light-producing apparatus and siren in a streamlined unit adaptable for application to the surface of a vehicle.

Numerous other objects and advantages will more fully appearduring the course and progress of the following specification. 10

Figure 1 shows a warning device, constructed in accordance with the present invention, mounte in place upon an automobile. y

Figure 2 is -a front elevation of the signal warn- 15 ing device shown in Figure 1.

Figure 3 is a sectional elevation taken on the line 3`3 in Figure 2.

Figure 4 is a detail plan elevation taken -on the line 4-4 in Figure 2.

The device, disclosed herein for the purpose of illustrating the present invention, is shown in Figure 1 as applied to the forward portion of the roof of an automobile and has a bracket IU which is secured to the vehicle roof through the agency of a pair of bolts I2. A pair of machine screws I4 in turn passes through the upper portion -of the bracket I0, as shown in Figure 3, and through apertures in the rear streamlined casing or shell I6, and are threaded in the block I8 which in turn is rigidly integral with the casing of the electric motor 20. It will be apparent, therefore, that the Weight of the motor andthe apparatus secured thereto is directly supported by the block I8 and the bracket I0. i

The motor 20 is. secured to a siren through the 35 agency of a flange'22 integral with'themotor casing, shown clearly in Figure -3. The siren proper comprises an outer, annular sheet wall 24 closed at its lefthand end, as viewed in Figure 3, by the wall 26 which is in turn fastened securely 40 to the ange 22 by means of the i machine screws 28. f

As shown in Figure 4, the annular wall member 24 is provided with a plurality of sound ports or apertures 30 from which the characteristic sound 45 of the siren emanates. The. shaft 32 of the electric motor extends through a suitable aperture in the wall 26 and is rigidly secured to the central bushing 34 of the impeller or rotor by suitable set screws. The impeller or rotor in turn comprises a circular wall 36, arranged transversely of the shaft 32, which terminates in the annular Wall 38 having an inwardly extending flange Dortion 40. v

The impeller is provided with a-plurality of radially extending vanes 42 which, when the impeller is rotated rapidly by the motor 20, direct columnsof air radially outwardly by centrifugal force. Spaced apertures in the wall 38, periodi- .locking connection 18 at cally coinciding with the apertures 30 in the annular wall 24, produce. thev lcharacteristic siren effect. A unitary casing 44 extends about the siren and, as will be readily apparent in Figure 3, is enlarged'in the vicinity of the ports 38, as shown at 46, toprovide the annular sound chamber 48.

The streamlined shell I6 enclosing the motor is provided at its forward end with an' annular L-shaped flange I1 which engages over the rearward edge of the casing 44 and is releasably secured thereto by machine screws, as shown in Fig. 4. Fcrwardly thereof the wall of the casing engages with the forward end of the annular wall 24 of the siren and extends outwardly as at 50 to form a barrel-like body portion which supports the lamp to be hereinafter described in detail.

In order that the sound produced within the annular sound chamber 48 may be liberated in a predetermined direction'from the device, there are provided integrally on either side of the casing curved walls 52 which provide a pair of ducts or conduits 54. These ducts communicate directly with the annular space 48 and are ared toward their forward end, as may be seen in Figure 4, where they are covered by a grating 56 to exclude debris and foreign matter.

Ihe intake air necessary for the operationl of the siren is drawn intothe device through the longitudinally extending apertures 58. It will be noted that'rthese inlet apertures, being formed on the underside of the casing, will not accumulate moisture and sleet since they are protected from above, not only by the superposed portions of the casing, but by the horizontally outwardlyextending walls 52 of the side ducts. Fine mesh screens 60 and 62 further protect the inlet and outlet apertures of the siren against particles of debris.

The flashing device is mounted in an aperture in the front face of the casing and comprises a concave or parabolic reflector 64 supported within the concave housing 66 to which is rigidly secured the lamp socket 68 supporting the lamp 10. The housing/66 is provided with an outwardly extending, L-shaped, annular flange formed about the periphery of the parabolic reflector 64 as well as the peripheral edge of the lens 14, this assembly being maintained in position by means of the annular rim member 'I6 of U-shaped section and having a releasable the bottom portion thereof.

The rim 1,6 is in turn maintained against the front wall of the housing member 44 by means of a concave spider or yoke member having three curved legs 88 rigidly secured to a collar 82 and connected to the projecting portion of the lamp socket 68 by means of the set screws 84. Attention is directed to the fact that this portion of the unit may be disassembled by releasing the set screws 84 whereupon the concave spider, including the legs 88 and the collar 82, may be slidably removed from the socket 68. Conversely, when assembling the device, the housing 88 together with the reector, lamp, socket, lens and assembled parts, are placed in the aperture in the front wall, as shown in Figure 3, after which the concave spider is placed over the socket portion 68 with the ends of the legs 80 adjacent the inner front wall of the casing 44, Tightening of the set screws 84 tends to maintain the assembly rigidly in the position shown.A

Wire conduits 86 and 88 extend from the lamp socket and the motor, respectively, to a suitable source of electric current (not shown) for controlling the operation of the device.

While the present invention comprehends the employment of various types of visible signalling devices, nevertheless, according to the preferred embodiment, the lamp 10 isintended to be connected with a suitable device for producing repeated flashing thereof in order to attract immediate attention thereto. Moreover, in this embodiment it is preferred that the motor and flashingydevice be connected for coincidental operation.

In use, actuation of a suitable control switch by the driver of the vehicle permits electric current to drive the motor 20 and accordingly the siren, liberating the sound or noise thereof in the annular space 48, whence it is directed forwardly through the parallel side ducts 54. yAt the same time the lamp 10 is illuminated.

Thepresent invention accordingly provides a compact and efficient device wherein, not only the light rays, but the sound waves are focused in a single direction. Accordingly the device may be mounted on `a vehicle so that the visual and sonic warning effects are emanated directly toward the persons to be warned; that is, in most cases, forwardly of the vehicle. Moreover, the operating parts of the siren are completely enclosed and protected against exterior weather conditions.

'I'he present invention will be readily adaptable to various other types of sound-producing, visual warning devices other than -those herein disclosed for purposes of illustration.

It is thought that the invention and numerous of its attendant advantages will be understood from the foregoing description and it is obvious that numerous changes may be' made in the form, construction and arrangement of the several parts without departing from the spirit or scope of the invention, or sacrificing any of its attendant advantages, the forml herein described being a preferred embodiment for the purpose of illustrating the invention.

The invention is hereby claimed as follows:

l. In signalling means, a siren comprising a cylindrical stator formed circumferentially with spaced ports, a housing element providing a guard having portions embracing the stator and forming a chamber extending forwardly of said stator,

channels communicating with said ports ancl positioned to direct the sound produced by the siren forwardly in the direction of the light rays.

2. In signalling means, a siren comprising a cylindrical stator formed circumferentially with spaced ports, a housing element providing a guard having portions embracing the stator and forming a chamber extending forwardly 4of said stator and communicating with and forming an air intake for said siren, means to support a light source on said housing element in position to transmit light rays in a direction forwardly of said chamber, said element forming also a plurality of sound outlet channels communicating with said ports and positioned to direct the sound produced by the siren forwardly in the direction of the light rays.

3. In signalling means, a siren comprising a cylindrical stator open at an end thereof and formed circumferentially with spaced ports, a housing element providing a guard having portions embracingl the stator and forming a chamber extending forwardly of said siren in communication with the said end of said stator, means to' support a light source on said housing element in position to transmit light rays in a direction forwardly 4of said chamber, said element forming also a pair of sound outlet channels on the opposite sides of said chamber communieating with said spaced ports and positioned to direct the sound produced by-the sirenforwardly in the direction of the light rays, said chamber being formed with an air inlet opening in a wall thereof extending between said channels.

4. In signalling means, a siren comprising a cylindrical stator formed circumferentially with spaced ports, a housing element providing a guard having an annular portion embracing said stator and forming a chamber extending forwardly of said stator, and means to support a light source in said chamber in a position to transmit light rays in a direction forwardly thereof, said element forming also anannular duct communicating with said spaced ports and a pluralityv of sound outlet channels communicating each at one end with said annular duct and positioned to direct the sound produced by .the siren forwardly in the direction of the light rays.

ROBERT DUNCAN. 

